(function (win){  
 var callboarTimer;  
 var callboard = $('#callboard');  
 var callboardUl = callboard.find('ul');  
 var callboardLi = callboard.find('li');  
 var liLen = callboard.find('li').length;  
 var initHeight = callboardLi.first().outerHeight(true);  

 win.autoAnimation = function (){  
	 if (liLen <= 1) return;  
	 var self = arguments.callee;  
	 var callboardLiFirst = callboard.find('li').first();  
	 callboardLiFirst.animate({  
		 marginTop:-initHeight  
	 }, 500, function (){  
		 clearTimeout(callboarTimer);  
		 callboardLiFirst.appendTo(callboardUl).css({marginTop:0});  
		 callboarTimer = setTimeout(self, 5000);  
	 });  
 }  

 callboard.mouseenter(  
	 function (){  
		 clearTimeout(callboarTimer);  
	 }).mouseleave(function (){  
		 callboarTimer = setTimeout(win.autoAnimation, 5000);  
	 });  
}(window));  